The present invention relates to a parking brake device, and in particular, to a parking brake device actuating by converting a rotating force to a linear movement, and being able to extend the length of stroke.
A parking brake device is generally used in order to prevent a parked vehicle from moving. In case of an Electronic Parking Brake device (EPB), it converts a rotating movement of a motor unit to a linear movement to thereby transmit braking force to the wheels of vehicle.
That is, when the electronic parking brake device drives the motor unit by actuating a switch or a lever, a bolt screw and a nut screw are moved according to rotating of the motor unit, and pull a brake cable connected to the bolt screw and the nut screw to generate a braking force.
In general, the parking brake device limits a stroke by a layout with the peripheral components, a shape of the nut screw and a coupling position of the brake cable, wherein the stroke is a relative moving distance between the nut screw and the bolt screw. Thus, the parking brake device has the problem that does not obtain the stroke sufficiently. Therefore, there is a need to improve the problem.
Meanwhile, Background Art of the present invention is disclosed in Korean Patent Laid-Open Publication No. 2009-0039056 (published on Apr. 22, 2009, Title of The Invention: Electronic Parking Brake system for Vehicle).